Google is the biggest company to truly understand the value of Open Source software.

Google Chrome was the first in line among many applications released by Google as Open Source.
Android is the world's most popular mobile platform.  Industry analysis IDC projects that by 2016 Android devices will outnumber traditional Windows PCs

Git is a free & open source, distributed version control system designed to handle everything from small to very large projects with speed and efficiency.
Projects using Git are: